1. Field of the Invention
The present invention relates to an X-ray computed tomography apparatus and, more particularly, to the functional maintenance of a slip ring system of an X-ray computed tomography apparatus.
2. Description of the Related Art
An X-ray computed tomography apparatus comprises a rotating frame section and fixed section, and radiates X-rays from an X-ray tube mounted on the rotating frame section onto a to-be-diagnosed object while rotating the rotating frame section, thus diagnosing the object.
Of such X-ray computed tomography apparatuses, an X-ray computed tomography apparatus having an X-ray generating system, e.g., an X-ray tube or a high-voltage generating device, mounted on a rotating frame section has recently become popular. In this apparatus having the X-ray generating system mounted on the rotating frame section, electric power is supplied to the X-ray generating system while a brush is brought into contact with a ring-like conductor, i.e., a slip ring, and their electrical coupling is maintained.
In the above-described apparatus, since the slip ring and the brush are mechanically in contact with each other, abrasion is caused on the slip ring and the brush upon rotation of the slip ring. The abrasion caused on the slip ring and the brush due to the contact with each other, and abrasion powder produced by the abrasion is a factor that increases the contact resistance between the slip ring and the brush. This increase in contact resistance causes a decrease in input voltage on the power-receiving member side, i.e., the X-ray generating system mounted on the rotating frame section, especially when electric power is transmitted through the slip ring and the brush. Therefore, an increase in contact resistance between the slip ring and the brush is a factor that degrades the performance of the X-ray computed tomography apparatus.
In order to compensate for the above-mentioned defect and maintain the high performance of the X-ray computed tomography apparatus, periodical maintenance is required. However, the performance of the X-ray computed tomography apparatus may not be satisfactorily maintained by performing only periodic maintenance, e.g., removal of abrasion powder by brushing the slip ring.
The reason why is that a contact resistance/abrasion is a phenomenon which is affected significantly by an operation environment, a frequency in use, etc.
As described above, since electric power is supplied to the X-ray generating unit or the like mounted on the rotating frame section by mechanically bringing the slip ring into contact with the brush, the high performance of the X-ray computed tomography apparatus cannot be maintained as sufficient electric power cannot be supplied to the rotating frame section with an increase in contact resistance between the slip ring and the brush.